This invention relates to passive infrared radiation actuated motion detection apparatus, and more particularly to a passive infrared (PIR) actuated switch assembly for controlling the operation of a functional device in response to detection of movement of a source of infrared radiation within an area monitored by the switch assembly.
Presently, the operation of electric lights is controlled by manually operated switches. Wall switches are provided for controlling the energization and deenergization of ceiling mounted lamps or lamps plugged into electrical receptacles wired to the wall switch. A person entering a darkened room must search for the wall switch to turn on the room light. In the instance where the person is carrying articles and does not have a free hand for searching for the wall switch, the person must enter the room and set down the articles before groping for the light switch. Similarly, when a person is about to leave a room carrying a number of items, the person must either turn off the light before picking up the items before leaving the room, or must leave the room light on.
It is common practice for persons leaving the room to leave the light on even though the person may not intend to return to the room. Thus, the room lights are maintained on even when they are not needed. This practice results in waste of energy.
Thus, it would be desirable to have an arrangement for controlling the energization of a room light automatically and instantly in response to a person entering a room and which provides for deenergization of the light when the person exits the room.